Telephone



(N0 Model.)

W/T/VESSES.

Patented Feb. f5, 188|.

(No Mo'del.) 2 Sheets-Sheet 2.

A. K. BATON. Telephone No. 237,838. Patented Feb. 15,1881.

vUi'vITED STATES Pivrl'zivrA OFFICE. l

ASAHEL-K. EATON, OF BROOKLYN, NEW YORK, lASSIGNOR TO EATON TELEPHONE COMPANY, OF NEW YORK.

FELEPHONE.

SPECIFICATION forming eert efl Lettere Patent Ne. 237,838, dated February 15, 1881.

an electro-magnetic telephone in which is involved the principle of the expansion and contraction of an iron or steel rod, or its equivalent, or by the making or breaking by the increase or diminution of the electric current carried around the rod, as hereinafter described. I etl'ect this by means of different forms of apparatus, illustrated in the accompanying drawings.

Figure 1 represents one of thesimplest forms Q f th i s invention, and consists of' a solid soft iron or steel bar, E, inclosed in a helix, F, ot' insulated wire. The plate D is of hard rubber, mica, wood', or anynon-magneticmaterial.

A magnet-diaphragm, or one capable ot' inducing magnetism, is wholly unnecessary, but of course may be used, its action being strictly mechanical.

It will be seen that thecentral bar is in direct contact with the diaphragm.

The principle involved in this instrumentis the one discovered by Professor Page-t'. c.,

nat when an electric current is allowed to now through acoil which includes a soft iron or steel core the core expands and contracts in length as the current is made or broken, producing a distinct click.

I nd that it is not essential that there should be an absolute makeandbreak action ofthe current, but that any modification of the'strength of the current will make itself heard in the central bar.

The diaphragm D is actuated directly by the pressure of the core upon its center, and repeats any sounds-such as vocal or instrumental music or articulate speech-transmitted to it through any of the dilerent forms ot transmitting apparat-us in use. The Reiss transmitter operates the instru men t quite satisfactorily. The form described, however, is the first and simplest produced, and has given place to others of a better character.

The bar E, Fig. 2, made up of tine iron wires, acts more ei'ectually than the solid core Application filed November 20, 1880. (No model.)

but this falls far-short of the action of the spiral bar E, Fig..3. This core l make ot' a spi-i ral closely wound, so that its successive turns are in absolute contact. The material ispret'f erably annealed pianowire. By this last del vice I obtain results that are very clear and distinct, and louder than when I use the ordi.- nary magneto telephone as a receiver. I have found that this apparatus may be also used as a transmitter. Its action in this respeen-is cxplainable on the supposition that y,

-the {fibrations of theplate I), which are produced by the impingement ot' the airwaves, are concentrated at the point where the plate is in contact with the core, and by setting up a molecular disturbance in the bar act to vary the current flowing through the coil F.

lIn Fig. 4 is shown a modification of my invention inwhich I use the form of a multipolar magnet for which I received Letters Patent dated May28,l878. [n this case, also, the cores may be solid and in direct contact with the non-magnetic diaphraglmor, as here shown, they may consist of closely-wound spirals constructed as before described.

Then desired, several spirals within the same coil may be used. In such a case they may be arranged in contact with the plate and in close contiguit-y, or they may be arranged one Within the other, and their ends may abut separately against the diaphragm, or may be attached to a common block or piece, against which the diaphragm rests.

I do not claim, broadly, a wire spiral as the core of the telephone-coil when arranged to impart movement to a diaphragm; nor do I claim to be the rst to communicate movement to a plate or diaphragm mechanically from the core oi' an electro-magnet, inasmuch as this has vheretofore been done; but in all cases ot which I am aware intermediate parts have been used between the core and the nonmagnetic plate.

l am aware thatthecore of amagnet hasbeen extended in the form of'a recurved spring bent around over the solid core and a non-magnetic diaphragm attached to the flat side of said spring. I am also aware that the core has been provided with an enlargement made in the form of atlanged head or disk, the pro- 5 also,

jecting ange or head resting in contact with a magnetic diaphragm or` armature, so as to leave a space for the to-and-fro movement ot' the diaphragm at, its center. .I am aware, that an open spiral to which is attached a diaphragm has been used as the core of a magnet. In all these devices the eonstruc- "tion is such that there is bodily movement to and fro of the parts in -response to magnetic attraction, whereas in my device I depend simply upon the linear expansion and contraction l .of the core due to the molecular changes consequent upon magnetization and demagnetization, as before explained.

What I claim as my invention is- '1. The combination of a niagnetizing coil or helix, a central rod orv bar, and aplate of nonmagnetic material transverse to said bar and in direct and solid contact with the end there- 2o of.

2. In a telephonie receiver, amagnetizing coil or helix inclosing a. closely-wound spiral of magnetizable'material the successive turns of which are in contact, substantially as described..

` 3. The combination, in a telephonie receiver, of a magnetizing-coil, an inclosed spiral closely wound, sothat its successive turns are in contact, and a sounding-plate, against which the end ot' said spiral impinges, substantially as described.

4. An electro-magnet whose coluor'helix embracesa closely-wound spiral the successive turns of vwhich are in contact, `substantially as described.

In testimony whereof I aix my signature in presence of two Witnesses.

ASAHEL K. EATON.

Witnesses:

H. 0.*ToWNsEND, JOHN J. DIFFLEY. 

